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Quality control tests are presented for resin matrix and carbon-carbon composites. Tests performed are filler test, resin test, prepregs test, and fabric test. The test results are presented in chart form.
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Cosmos 2044 was launched on September 15, 1989, containing radiation dosimetry experiments and a biological payload including two young male rhesus monkeys, ten adult male Wistar rats, insects, amphibians, protozoa, cell cultures, worms, plants and fish. The biosatellite was launched from the Plesetsk Cosmodrome in the Soviet Union for a mission duration of 14 days, as planned. The major research objectives were: (1) Study adaptive response mechanisms of mammals during flight; (2) Study physiological mechanisms underlying vestibular, motor system and brain function in primates during early and later adaptation phases; (3) Study the tissue regeneration processes of mammals; (4) Study the development of single-celled organisms, cell cultures and embryos in microgravity; (5) Study radiation characteristics during the mission and investigate doses, fluxes and spectra of cosmic radiation for various types of shielding. American and Soviet specialists jointly conducted 29 experiments on this mission including extensive preflight and post flight studies with rhesus monkeys, and tissue processing and cell culturing post flight. Biosamples and data were subsequently transferred to the United States. The U.S. responsibilities for this flight included development of flight and ground-based hardware, the preparation of rat tissue sample procedures, the verification testing of hardware and experiment procedures, and the post flight analysis of biospecimens and data for the joint experiments. The U.S. investigations included four primate experiments, 24 rat experiments, and one radiation dosimetry experiment. Three scientists investigated tissue repair during flight for a subgroup of rats injured preflight by surgical intervention. A description of the Cosmos 2044 mission is presented in this report including preflight, on-orbit and post flight activities. The flight and ground-based bioinstrumentation which was developed by the U.S. and U.S.S.R. is also described, along with the associated preflight testing of the U.S. hardware.
Future large infrared space telescopes will require cooling to 4K to achieve background limited performance for submillimeter wavelengths. These observatories will require lifetimes of many years and will have relatively large cooling requirements making stored helium dewars impractical. We have designed and are building an adiabatic demagnetization refrigerator (ADR) for use in cooling relatively large loads (10- 100 mW) at 4K and rejecting that heat to a cryocooler operating at 1 OK. Cryocoolers below 1 OK have poor thermodynamic efficiency and ADRs can operate in this temperature range with an efficiency of 75% of Carnot or better. Overall, this can save as much as 2/3 of the input power required to operate a 4K cryocooler. The ADR magnet consists of 8 short coils wired in series and arranged in a toroid to provide self shielding of its magnetic field. This will save mass (about 30% of the mass or about 1.5 kg in our small version, higher percentages in higher cooling power, larger versions) that would have been used for passive or active shields in an ordinary solenoid. The toroid has a 100 mm outer diameter and will produce an approximately 3T average field. In the initial demonstration model the toroid coils will be wound with ordinary NbTi wire and operated at 4K. A second version will then use Nb3Sn wire to provide complete 10K operation. As a refrigerant for this temperature range we will use either GdLiF4 or GdF3 crystals, pending tests of these crystals' cooling capacity per field and thermal conductance. Preliminary indications are that these materials are superior to GGG. We will use gas gap heat switches to alternately connect the toroid to the cold load and the warm heat sink. A small continuous stage will maintain the cold end at 4K while the main toroid is recycled.
We present measurements of He-broadening parameters for the R(0) and O(2) lines in the fundamental band of 13CO at different temperatures between 12K and room temperature. The broadening parameters are determined, taking into account confinement narrowing, by simultaneous least-squares fitting of spectra recorded using a frequency stabilized diode laser spectrometer. The pressure broadening cross sections are deduced and compared to close-coupling calculations and earlier results obtained for rotational transitions of 12 CO.
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The GlueX experiment housed in Hall D of the Thomas Jefferson National Laboratory was created to map the light meson spectrum in order to contribute to the Standard Model of particle physics by strengthening our understanding of the strong interaction. GlueX is a medium-energy photoproduction experiment that utilizes a linearly polarized photon beam to create hadronic forms of matter.
Abstract Despite the observation of significant suppressions of $$b\rightarrow s\mu ^+\mu ^-$$ b → s μ + μ - branching ratios no clear sign of New Physics (NP) has been identified in $$\Delta F=2$$ Δ F = 2 observables $$\Delta M_{d,s}$$ Δ M d , s , $$\varepsilon _K$$ ε K and the mixing induced CP asymmetries $$S_{\psi K_S}$$ S ψ K S and $$S_{\psi \phi }$$ S ψ ϕ . Assuming negligible NP contributions to these observables allows to determine CKM parameters without being involved in the tensions between inclusive and exclusive determinations of $$|V_{cb}|$$ | V cb | and $$|V_{ub}|$$ | V ub | . Furthermore this method avoids the impact of NP on the determination of these parameters present likely in global fits. Simultaneously it provides SM predictions for numerous rare K and B branching ratios that are most accurate to date. Analyzing this scenario within $$Z^\prime $$ Z ′ models we point out, following the 2009 observations of Monika Blanke and ours of 2020, that despite the absence of NP contributions to $$\varepsilon _K$$ ε K , significant NP contributions to $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ , $$K_{L}\rightarrow \pi ^0\nu {\bar{\nu }}$$ K L → π 0 ν ν ¯ , $$K_S\rightarrow \mu ^+\mu ^-$$ K S → μ + μ - , $$K_L\rightarrow \pi ^0\ell ^+\ell ^-$$ K L → π 0 ℓ + ℓ - , $$\varepsilon '/\varepsilon $$ ε ′ / ε and $$\Delta M_K$$ Δ M K can be present. In the simplest scenario, this is guaranteed, as far as flavour changes are concerned, by a single non-vanishing imaginary left-handed $$Z^\prime $$ Z ′ coupling $$g^L_{sd}$$ g sd L . This scenario implies very stringent correlations between the Kaon observables considered by us. In particular, the identification of NP in any of these observables implies automatically NP contributions to the remaining ones under the assumption of non-vanishing flavour conserving $$Z^\prime $$ Z ′ couplings to $$q{\bar{q}}$$ q q ¯ , $$\nu {\bar{\nu }}$$ ν ν ¯ , and $$\mu ^+\mu ^-$$ μ + μ - . A characteristic feature of this scenario is a strict correlation between $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ and $$K_{L}\rightarrow \pi ^0\nu {\bar{\nu }}$$ K L → π 0 ν ν ¯ branching ratios on a branch parallel to the Grossman-Nir bound. Moreover, $$\Delta M_K$$ Δ M K is automatically suppressed as seems to be required by the results of the RBC-UKQCD lattice QCD collaboration. Furthermore, there is no NP contribution to $$K_L\rightarrow \mu ^+\mu ^-$$ K L → μ + μ - which otherwise would bound NP effects in $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ . Of particular interest are the correlations of $$K^+\rightarrow \pi ^+\nu {\bar{\nu }}$$ K + → π + ν ν ¯ and $$K_{L}\rightarrow \pi ^0\nu {\bar{\nu }}$$ K L → π 0 ν ν ¯ branching ratios and of $$\Delta M_K$$ Δ M K with the ratio $$\varepsilon '/\varepsilon $$ ε ′ / ε . We investigate the impact of renormalization group effects in the context of the SMEFT on this simple scenario.
We present the results of the first Dalitz plot analysis of the decay D 0 → K – π + η . The analysis is performed on a data set corresponding to an integrated luminosity of 953 fb – 1 collected by the Belle detector at the asymmetric-energy e + e – KEKB collider. The Dalitz plot is well described by a combination of the six resonant decay channels K ¯ * ( 892 ) 0 η , K – a 0 ( 980 ) + , K – a 2 ( 1320 ) + , K ¯ * ( 1410 ) 0 η , K * ( 1680 ) – π + and K 2 * ( 1980 ) – π + , together with K π and K η S-wave components. The decays K * ( 1680 ) – → K – η and K 2 * ( 1980 ) – → K – η are observed for the first time. We measure ratio of the branching fractions, B ( D 0 → K – π + η ) B ( D 0 → K – π + ) = 0.500 ± 0.002 ( stat ) ± 0.020 ( syst ) ± 0.003 ( B PDG ) . Using the Dalitz fit result, the ratio B ( K * ( 1680 ) → K η ) B ( K * ( 1680 ) → K π ) is measured to be 0.11 ± 0.02 ( stat ) – 0.04 + 0.06 ( syst ) ± 0.04 ( B PDG ) ; this is much lower than the theoretical expectations ( ≈ 1 ) made under the assumption that K * ( 1680 ) is a pure 1 3 D 1 state. The product branching fraction B ( D 0 → [ K 2 * ( 1980 ) – → K – η ] π + ) = ( 2. 2 – 1.9 + 1.7 ) × 10 – 4 is determined. In addition, the π η ' contribution to the a 0 ( 980 ) ± resonance shape is confirmed with 10.1 σ statistical significance using the three-channel Flatté model. We also measure B ( D 0 → K ¯ * ( 892 ) 0 η ) = ( 1.4 1 – 0.12 + 0.13 ) % . This is consistent with, and more precise than, the current world average ( 1.02 ± 0.30 ) % , deviates with a significance of more than 3 σ from the theoretical predictions of (0.51–0.92)%.
K is alpha Samarium structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are five inequivalent K sites. In the first K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are six shorter (4.63 Å) and six longer (4.79 Å) K–K bond lengths. In the second K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are three shorter (4.64 Å) and six longer (4.79 Å) K–K bond lengths. In the third K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are six shorter (4.63 Å) and six longer (4.79 Å) K–K bond lengths. In the fourth K site, K is bonded to twelve K atoms to form a mixture of distorted face, edge, and corner-sharing KK12 cuboctahedra. There are three shorter (4.64 Å) and six longer (4.79 Å) K–K bond lengths. In the fifth K site, K is bonded to sixteen K atoms to form a mixture of distorted face, edge, and corner-sharing KK16 cuboctahedra. There are a spread of K–K bond distances ranging from 4.79–9.58 Å.
K(O3I)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.75–2.91 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.66–3.05 Å. There are twelve inequivalent O sites. In the first O site, O is bonded in a 3-coordinate geometry to two equivalent K and one I atom. The O–I bond length is 1.83 Å. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.78 Å. In the third O site, O is bonded in a 1-coordinate geometry to two K and one I atom. The O–I bond length is 1.82 Å. In the fourth O site, O is bonded in a distorted trigonal planar geometry to one K and two I atoms. There are one shorter (1.97 Å) and one longer (2.14 Å) O–I bond lengths. In the fifth O site, O is bonded in a distorted trigonal non-coplanar geometry to one K and two I atoms. There are one shorter (1.91 Å) and one longer (2.27 Å) O–I bond lengths. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent K and two I atoms. There are one shorter (1.82 Å) and one longer (2.75 Å) O–I bond lengths. In the seventh O site, O is bonded in a distorted trigonal non-coplanar geometry to two K and one I atom. The O–I bond length is 1.83 Å. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one K and one I atom. The O–I bond length is 1.82 Å. In the ninth O site, O is bonded in a bent 150 degrees geometry to one K and one I atom. The O–I bond length is 1.78 Å. In the tenth O site, O is bonded in a distorted trigonal planar geometry to one K and two I atoms. There are one shorter (1.88 Å) and one longer (2.28 Å) O–I bond lengths. In the eleventh O site, O is bonded in a 1-coordinate geometry to one K and two I atoms. There are one shorter (1.87 Å) and one longer (2.37 Å) O–I bond lengths. In the twelfth O site, O is bonded in a 3-coordinate geometry to one K and two I atoms. There are one shorter (1.81 Å) and one longer (2.60 Å) O–I bond lengths. There are four inequivalent I sites. In the first I site, I is bonded in a distorted trigonal non-coplanar geometry to three O atoms. In the second I site, I is bonded in a distorted trigonal non-coplanar geometry to three O atoms. In the third I site, I is bonded in a distorted octahedral geometry to six O atoms. In the fourth I site, I is bonded in a 6-coordinate geometry to six O atoms.
K is alpha structured and crystallizes in the cubic I-43m space group. The structure is three-dimensional and consists of two potassium molecules and one K framework. In the K framework, there are three inequivalent K sites. In the first K site, K is bonded in a trigonal non-coplanar geometry to three equivalent K atoms. All K–K bond lengths are 4.59 Å. In the second K site, K is bonded in a 6-coordinate geometry to eight K atoms. There are a spread of K–K bond distances ranging from 4.23–4.80 Å. In the third K site, K is bonded in a 8-coordinate geometry to eight K atoms. Both K–K bond lengths are 4.76 Å.
Small-conductance (K Ca 2.2) and intermediate-conductance (K Ca 3.1) Ca 2+ -activated K + channels are gated by a Ca 2+ -calmodulin dependent mechanism. NS309 potentiates the activity of both K Ca 2.2 and K Ca 3.1, while rimtuzalcap selectively activates K Ca 2.2. Rimtuzalcap has been used in clinical trials for the treatment of spinocerebellar ataxia and essential tremor. We report cryo-electron microscopy structures of NS309-bound K Ca 2.2 and K Ca 3.1, in addition to structures of rimtuzalcap-bound K Ca 2.2 and mutant K Ca 3.1_R355K. The different conformations of calmodulin and the cytoplasmic HC helices in the two channels underlie the subtype-selectivity of rimtuzalcap for K Ca 2.2. NS309 binds to pre-existing pockets in both channels, while the bulkier rimtuzalcap binds in an induced-fit pocket in K Ca 2.2 requiring conformational changes. In K Ca 2.2, calmodulin’s N-lobes are sufficiently far apart to enable conformational changes to accommodate either NS309 or rimtuzalcap. In K Ca 3.1, calmodulin’s N-lobes are closer to each other and constrained by K Ca 3.1’s HC helices, which allows binding of NS309 but not rimtuzalcap. Replacement of arginine-355 in K Ca 3.1’s HB helix with lysine (K Ca 3.1_R355K) allows the binding of rimtuzalcap and renders the mutant channel sensitive to rimtuzalcap. These structures provide a framework for structure-based drug design targeting K Ca 2.2 channels.
K2(BH)9BH crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of four boranediylradical molecules and one K2(BH)9 framework. In the K2(BH)9 framework, there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight H atoms. There are a spread of K–H bond distances ranging from 2.67–3.05 Å. In the second K site, K is bonded in a 8-coordinate geometry to eight H atoms. There are a spread of K–H bond distances ranging from 2.79–3.07 Å. There are nine inequivalent B sites. In the first B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the second B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the third B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the fourth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the fifth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.20 Å. In the sixth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.20 Å. In the seventh B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the eighth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. In the ninth B site, B is bonded in a distorted single-bond geometry to one H atom. The B–H bond length is 1.21 Å. There are nine inequivalent H sites. In the first H site, H is bonded in a distorted bent 120 degrees geometry to one K and one B atom. In the second H site, H is bonded in a single-bond geometry to two K and one B atom. In the third H site, H is bonded in a distorted single-bond geometry to two equivalent K and one B atom. In the fourth H site, H is bonded in a distorted single-bond geometry to two K and one B atom. In the fifth H site, H is bonded in a single-bond geometry to two equivalent K and one B atom. In the sixth H site, H is bonded in a distorted single-bond geometry to two equivalent K and one B atom. In the seventh H site, H is bonded in a distorted single-bond geometry to two K and one B atom. In the eighth H site, H is bonded in a distorted single-bond geometry to one K and one B atom. In the ninth H site, H is bonded in a single-bond geometry to two K and one B atom.
K(O3I)2 crystallizes in the orthorhombic Fdd2 space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.70–3.17 Å. In the second K site, K is bonded in a body-centered cubic geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.87–3.07 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one I atom. The O–I bond length is 1.81 Å. In the second O site, O is bonded in a 1-coordinate geometry to one K and two I atoms. There are one shorter (1.88 Å) and one longer (2.38 Å) O–I bond lengths. In the third O site, O is bonded in a 1-coordinate geometry to one K and one I atom. The O–I bond length is 1.83 Å. In the fourth O site, O is bonded in a 4-coordinate geometry to two equivalent K and two I atoms. There are one shorter (1.85 Å) and one longer (2.61 Å) O–I bond lengths. In the fifth O site, O is bonded in a 4-coordinate geometry to two K and two I atoms. There are one shorter (1.84 Å) and one longer (2.68 Å) O–I bond lengths. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent K and one I atom. The O–I bond length is 1.83 Å. In the seventh O site, O is bonded in a distorted single-bond geometry to one K and one I atom. The O–I bond length is 1.91 Å. In the eighth O site, O is bonded in a 1-coordinate geometry to one K and one I atom. The O–I bond length is 1.89 Å. In the ninth O site, O is bonded in a 4-coordinate geometry to two K and two I atoms. There are one shorter (1.85 Å) and one longer (2.63 Å) O–I bond lengths. There are three inequivalent I sites. In the first I site, I is bonded in a 5-coordinate geometry to three O atoms. In the second I site, I is bonded in a 6-coordinate geometry to five O atoms. In the third I site, I is bonded in a 3-coordinate geometry to five O atoms.
K(TeO3)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent K sites. In the first K site, K is bonded in a 8-coordinate geometry to eight O atoms. There are a spread of K–O bond distances ranging from 2.94–3.16 Å. In the second K site, K is bonded in a 1-coordinate geometry to three O atoms. There are one shorter (2.54 Å) and two longer (2.91 Å) K–O bond lengths. There are five inequivalent Te sites. In the first Te site, Te is bonded to six O atoms to form corner-sharing TeO6 octahedra. The corner-sharing octahedral tilt angles are 48°. There is two shorter (1.83 Å) and four longer (2.05 Å) Te–O bond length. In the second Te site, Te is bonded to five O atoms to form corner-sharing TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 40–62°. There are a spread of Te–O bond distances ranging from 1.96–2.28 Å. In the third Te site, Te is bonded to six O atoms to form TeO6 octahedra that share corners with four equivalent TeO6 octahedra and corners with two equivalent TeO5 square pyramids. The corner-sharing octahedral tilt angles are 46°. All Te–O bond lengths are 1.95 Å. In the fourth Te site, Te is bonded to six O atoms to form TeO6 octahedra that share corners with four TeO6 octahedra and corners with two equivalent TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 45–48°. There are a spread of Te–O bond distances ranging from 1.94–1.99 Å. In the fifth Te site, Te is bonded to six O atoms to form TeO6 octahedra that share corners with four TeO6 octahedra and corners with two equivalent TeO5 square pyramids. The corner-sharing octahedra tilt angles range from 41–46°. There are a spread of Te–O bond distances ranging from 1.90–2.01 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a 2-coordinate geometry to two Te atoms. In the second O site, O is bonded in a 2-coordinate geometry to one K and two Te atoms. In the third O site, O is bonded in a bent 150 degrees geometry to one K and one Te atom. In the fourth O site, O is bonded in a 2-coordinate geometry to one K and two equivalent Te atoms. In the fifth O site, O is bonded in a distorted bent 150 degrees geometry to two equivalent Te atoms. In the sixth O site, O is bonded in a distorted trigonal planar geometry to one K and two Te atoms. In the seventh O site, O is bonded in a 4-coordinate geometry to two K and two Te atoms. In the eighth O site, O is bonded in a distorted bent 120 degrees geometry to one K and two Te atoms.
Abstract Hydraulic conductivity ( K ) is a key hydrologic parameter widely recognized to be difficult to estimate and constrain, with little consistent assessment in disturbed, urbanized soils. To estimate K , it is either measured, or simulated by pedotransfer functions, which relate K to easily measured soil properties. We measured K in urbanized soils by double‐ring infiltrometer ( K dring ), near‐saturated tension infiltrometry ( K minidisk ), and constant head borehole permeametry ( K borehole ), along with other soil properties across the major soil orders in 12 United States cities. We compared measured K with that predicted from the pedotransfer function, ROSETTA. We found that regardless of soil texture, K dring was consistently larger than K minidisk ; with the latter having slightly less sample variance. K borehole was dependent upon specific subsurface conditions, and contrary to common expectations, did not always decrease with depth. Based on either soil textural class, or percent textural separates (sand, silt clay), ROSETTA did not accurately predict measured K for surface nor subsurface soils. We go on to discuss how K varies in urban landscapes, the role of measurement methods and artifacts in the perception of this metric, and implications for hydrologic modeling. Overall, we aim to inspire consistency and coherence when addressing K ‐related challenges in sustainable urban water management.